1. Technical Field
The present disclosure relates to an optical disk on which data is optically recorded and a device for recording and playing back data on and from the optical disk.
2. Description of the Related Art
Techniques that improve recording density per volume in optical disks include a land (inter-groove)-groove recording and playback technique that is capable of improving recording density of tracks. Although data has been conventionally recorded only on a groove or a land, this technique, which has been already used in a DVD-RAM, records data on both a groove and a land to improve recording density of a track.
In the DVD-RAM, however, since a data recording area and an address area are provided in a track, format efficiency is not good, and this causes waste of a data recording area. In order to cope with this problem, PTL 1 discloses a technique with which address information is recorded by wobblings of a groove track, and thus waste of a data recording area is not caused.